Anemia is one of the major reasons why patients present with shortness of breath, fatigue, pallor and weakness in clinics. Anemia is a reduction of the oxygen carrying capacity of the blood that results in decreased oxygen supply to tissue cells. It is of utmost importance for doctors to rule out anemia as a cause of this range of symptoms as not giving prompt medical treatment can result in severer symptoms and even fatality.

00:01
Now moving forward, apart
from acute blood lossand still in the realm of
normocytic non-hemolytic anemia,let us now move in
to the bone marrow.
00:11
And for whatever reason,
we’re going to shut it down.
00:14
If you shut down your bone
marrow, then what happens?Well you can’t produce
reticulocytes, can you?So therefore,
what’s the concept?It’s the fact that you have a decreased
reticulocyte production indexor as it says here
inadequate reticulocytosis.
00:29
And that magic corrected
reticulocyte number is less than 3%.
00:35
That you’ll have to memorize
but the concept is clear.
00:38
It’s a fact that the bone
marrow has been shut down.
00:42
Why?Well, we’ll get into
this in a second.
00:44
Bone marrow cellularity rule-of-thumb.
00:47
So if the bone marrow has been shut down,think about what the bone
marrow should look like.
00:51
It should be nice and empty.
00:52
There should be lipid.
00:54
There should be fat vacuoles and obviously,
there should be hematopoietic stem cells.
00:58
And there should be those
primitive type of blasts, right?Now, not too much and not
too little, just right.
01:07
And so that you can then produce a
proper homeostatic churning or synthesisof the stem cells
that we require.
01:15
However, if the bone marrow
for whatever reason,let’s say that this patient
has aplastic anemia,then understand that at this point,
the bone marrow is completely deadand is pretty empty.
01:24
I’ll show you pictures.
01:26
Now, as a rule-of-thumb which
you can use as 100 minus agegives you approximate normal
cellularity of your bone marrow.
01:33
Just the generality, but as far
as your concern, it would work.
01:38
Now the causes, what’s
causing aplastic anemia?What is then causing the bone marrow
to become aplastic or hypocellular?Well, pancytopenia is just a term
that we use for what, please?Usually it’s in reference
to the trilineage.
01:54
And by trilineage we are referring to,
obviously, the RBCs,the platelets.
01:59
And of all the granulocytes,which one do we normally have in our
body circulating predominantly?Good, neutrophils.
02:07
So that’s usually what you were
referring to when you say pancytopeniaand each one of those loss of the lineagesis going to give you different
symptoms in your patient.
02:15
For example, if there is no RBC, your
patient is going to present how?
Fatigued and tired.
02:21
If your patient has not enough
platelets, what is that presenting with?Obviously excess bleeding
that can form a clot.
02:30
And if they don’t have neutrophils,
what does that mean to you?Oh, they are now
susceptible to infection.
02:38
Those are three that you want to take
a look at when you have pancytopenia.
02:41
Earlier, we have talked about this in
terms of megaloblastic anemia, right?In megaloblastic anemia, remember please,you were still producing your
cells but they were blasts.
02:54
But just because you’ve formed a cell,if it hasn’t matured then it can’t
carry out its function, can it?Of course not.
03:03
So those megaloblastic anemia
or the megaloblastic cellsand hypersegmented neutrophils
with B12 and folate,yes, there is pancytopenia but
that is not aplastic anemia.
03:13
Is that clear?By definition, if it’s aplastic anemia,it means that you had
no cells being producedbecause the bone marrow
had been shut downand so therefore in the category of
normocytic non-hemolytic anemia.
03:25
Keep that in mind as
you move forward.
03:29
Now bone marrow failure,
idiopathic/autoimmune being the most common.
03:32
You find that occurring
with many organ damage.
03:36
Drugs including chloramphenicol
and chemotherapy.
03:39
Chemosuppression, right, in general
or bone marrow suppression.
03:43
Usually looking at those
cells that like to divide.
03:45
Tell me about your stem cells.
03:47
What kind of cells are they?They are labile, aren't they?They love to proliferate,
proliferate, proliferate.
03:53
And so therefore with chemotherapy, looking
at those cells that love to proliferateand unfortunately instead of attacking the
cancer, may also have collateral damage.
04:01
You’ve heard of bone
marrow suppression.
04:03
You’ve heard of hair loss.
04:04
And there is massive diarrhea, isn't there?In those patients that are taking
chemotherapy unfortunately.
04:09
Quite a bit of pain.
04:10
Sometimes the chemo is worse
than the disease itself.
04:14
Infection, we have parvovirus B19.
04:16
Now, what we’ll do here, is well, is
anytime parvovirus --is it possible that you might have a
patient that has another type of anemiasuch as hemolytic anemia and then may then
have a parvovirus B19 virus infection?Sure.
04:31
And so therefore, at that
point, where do you move in to?What’s my topic here or category?Normocytic non-hemolytic because the
bone marrow has been shut down.
04:40
Now, with Diamond-Blackfan syndrome,
we’ll talk about this a little bit more.
04:44
But what I do wish for you to
keep in mind is the following.
04:47
Diamond-Blackfan syndrome can come
under either your bone marrow failurewhere this is normocytic
non-hemolyticand please be careful
because Diamond-Blackfancould also be part of your
megaloblastic anemia.
04:59
We’ll talk more about that later.
05:00
But that is one that you
want to pay attention to.
05:03
Fanconi’s anemia, there, what
you want to pay attention tois do not confuse that
with Fanconi’s syndromewhich is a problem with the proximal
convoluted tubule in the kidney.
05:12
One has nothing to do with the other.
05:14
These are all the different causes that
you want to be quite familiar withwith bone marrow failure.
05:20
So what is Diamond Blackfan syndrome?

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